Objective:To study the MR spectroscopic characteristics of orbital tumors and normal tissues in vitro by the super high field MR,so as to provide theoretical basis for clinical application of MR spectroscopy(MRS).Methods: Ten tumor specimens(including 7 benign ones and 3 malignant ones) and 2 normal tissue samples received MR spectroscopic examination by BRUKER AVANCE 400(SB)super high field MR,and their MR spectroscopic characteristics were compared.Results: ~(1)H-MRS with super high field MR showed that the Cho and Cr peaks of malignant orbital tumors were higher than those of benign tumors.Three consecutive single peaks were noticed around 2?10~(-6) in the MRS of benign and malignant tumors,but not in that of normal tissues.Conclusion: ~(1)H-MRS can differentiate benign,malignant orbital tumors and normal tissues,making it worth of further study for clinical application.

ObjectiveTo investigate the manifestation and diagnostic value of MRI in the patients with non-thyroid-related exophthalmos.Methods One hundred and sixty-eight patients with non-thyroidrelated exophthalmos confirmed by histopathology underwent MRI examination using 8-channel phased array head coil.Of 168 patients,165 underwent contrast-enhanced MRI.Results Of the 168 cases,68 were hemangioma,34 were lymphoma,14 were pleomorphic adenoma of the lacrimal gland,12 were inflammatory pseudotumor,6 were adenoid cystic carcinoma of the lacrimal gland,6 were schwannoma,5 were dermoid cyst,5 were meningioma,3 were solitary fibrous tumor,2 were optic nerve glioma,2 were embryonal rhabdomyosarcoma,2 were lipoma,et al.Of the 165 enhanced cases,the MRI diagnosis was in accordance with surgical pathology findings in 111 cases (67.3％ ).The tumor was hemangioma in 65,lymphoma in 22,pleomorphic adenoma of the lacrimal gland in 10,inflammatory pseudotumor in 5,meningioma in 3,adenoid cystic carcinoma of the lacrimal gland in 3,optic nerve glioma in 1,schwannoma in 1,and dermoid cyst in 1.Eleven cases simultaneously had dynamic contrast-enhanced (DCE) MRI,the MRI diagnosis was consistent with pathological findings in 10 cases,which included 7 hemangioma,2 lymphoma,and 1 meningioma.The time-intensity curves of DCE-MRI showed persistent enhancement type,rapidly enhancing and rapid wash-out and plateau-shaped type,and rapidly enhancing and rapid wash-out,respectively.Three cases showed soft tissue mass on only plain MRI.ConclusionsThe conventional orbital MRI can explore the causes of proptosis,which is helpful to determine the location and nature of the mass.Enhanced and DCE MRI can further observe blood supply of the lesions.

Objective To analyze and summarize the characteristics of thyroid diseases on the MR diffusion-weighted imaging.Methods Forty-two patients with thyroid lesions,including 10 males and 32 females [age range 20-72 years,mean age (42 + 13) years] underwent MR DWI before surgery and biopsy.The diagnoses of thyroid lesions were confirmed by pathological results.ADC values of benign and malignant nodules,with different b values (b values was 300,500 and 800 s/mm2),were generated by using post-processing software Functool of GE company(USA).The independent-samples t test was used and ROC curve was made to evaluate the diagnostic efficiency of the ADC values by using statistical software SPSS 12.0.Results Histologically,there were 28 benign lesions and 14 malignant lesions.Benign lesions included 20 cases of thyroid adenoma,6 cases of nodular goiter and 2 cases of Hashimoto's thyroiditis respectively.Malignant lesions consisted of 11cases of thyroid papillary carcinoma,2 cases of follicular thyroid cancer,and 1case of dysplasia.mean ADC value of benign thyroid lesions was (2.39 ±0.38) ×10 -3 mm2/s and mean ADC value of malignant thyroid lesions was ( 1.60 ± 0.56) × 10 -3 mm2/s with b value of 300 s/mm2.The statistical difference was significant between them( t =5.35,P ＜ 0.05 ).The statistical difference of mean A DC values,between benign and malignant nodules with b value of 500 s/mm2 [ (1.85 +0.33 ) × 10 -3 mm2/s and ( 1.65 ± 0.42 ) × 10 -3 mm2/s ],was insignificant ( t =1.70,P ＞ 0.05 ).The statistical difference of mean ADC values,between benign and malignant nodules with b value of 800 s/mm2 [ ( 1.61± 0.30) × 10 -3mm2/s and( 1.44 +0.29) × 10 -3mm2/s],was insignificant (t =1.76,P ＞0.05 ).ROC curve indicated that the ADC value of 1.98 × 10-3 mm2/s or higher was the cut-off value for differentiating benign from malignant cold thyroid nodules,with a sensitivity of 85.7％,and a specificity of 78.6％.Conclusions The image quality is best with b value of 300 s/mm2.Mean ADC value of benign lesions was significantly higher than mean ADC value of malignant lesions with b value of 300 s/mm2.

Objective To evaluate the correlation between cerebral blood flow(CBF)with age and gender with arterial spin labe-ling in magnetic resonance imaging.Methods All thirty-seven healthy volunteers were divided into A(20-29 years,n=10),B(30-39 years,n=9),C(40-49 years,n=9)and D(50-59 years,n=9),underwent conventional MRI and ASL(Q2TIPS)examination. Cerebral blood flow (CBF)maps were obtained and reviewed.ROIs were respectively selected in bilateral cerebral hemispheres and CBF values were generated.The comparison of CBF value between the left and right hemispheres and within the four age group differences were performed.The relationships between CBF values with age and gender were also analyzed.Results There was no statistical difference of CBF in white or gray matter between bilateral hemispheres in all groups (P > 0.05).A significant positive correlation was found between age and CBF values of the left whole brain (r=0.378,P =0.020)in group C,while no significant difference of CBF in bilateral gray matter,white matter or whole brain was detected among all age groups (P > 0.05).There was no statistical difference of CBF between male and female volunteers (P > 0.05).Conclusion Quantitative estimates of CBF can be obtained with ASL sequence.The preliminary results suggest that CBF values do not significantly associated with age or gender.

Objective To discuss the application value of texture analysis of conventional MRI in differential diagnosis of orbital lymphoma from inflammatory pseudotumor.Methods The conventional MRI data of 15 patients with lymphoma and 17 patients with inflammatory pseudotumor proven by pathology or clinical follow-up were retrospectively reviewed.The texture features of lesions based on axial T1WI,fat-saturated T2WI and contrast enhanced fat-saturated T1WI were extracted by manually drawn ROIs with software MaZda.The subsets of optimized texture parameters were chosen by four different methods:Fisher coefficient,probability of classification error and average correlation coefficient (POE+ ACC),mutual information measure (MI) and the combination of the above three methods (FPM),respectively.Linear discriminant analysis (LDA) and nonlinear discriminant analysis (NDA) were performed for texture classification.The texture features from the sequence with the best classification result of orbital lymphoma and inflammatory pseudotumor were compared.Results The optimal texture parameters were mainly derived from co occurrence matrix and run-length matrix on T1WI and T2WI.The optimal texture parameters were mainly derived from co-occurrence matrix and histogram on contrast enhanced T1WI.The best classification of MRI texture was obtained within T2WI with lowest classification error of 1.56％ achieved by FPM in combination with NDA.Comparing the texture parameters of orbital lymphoma and inflammatory pseudotumor on T2WI,the angular second moment and long length emphasis were significantly higher in orbital lymphoma (both P＜0.005),while the entropy and short length emphasis were significantly lower in orbital lymphoma (both P＜0.005).Conclusion It is feasible to use texture analysis on conventional MRI for the differentiation of orbital lymphoma and inflammatory pseudotumor.

0) and the correlation coefficient were low.The absence of intravesical occurrence of the cancer in solitary primary tumor cases was significantly less than that in the multiple ones ( P =0).The intravesical occurrence rate of the cancer elevated with the pathological stage of the primary cancer ( P =0.0039).92.5% of cases with initial concurrent involvement of the bladder have had the occurrence of bladder cancer within 2 years after surgical treatment. Conclusions The number and the stage of the primary tumor,with concurrent bladder involvement or not and the internal between the occurrence of the bladder cancer and the upper urinary tract cancer are the significant factors for prognosis,the coefficient correlation between the 4 factors being low.

Objective To investigate the diagnostic significance of presumed circle area retio(PCAR) measured by TRUS in detecting bladder outlet obstruction (BOO) from BPH. Methods 78 cases of BPH aged from 62～78 with IPSS 22.0?2.2 were studied from June of 2000 to June of 2001. Prostate volume, Transition zone index(TZI) and PCAR were measured with TRUS. Urodynamics were conducted, including Qmax, P det.Qmax and AG number. The correlation analysis was performed. Results TZI(0.48?0.15) and PCAR (0.72?0.10) were both closely related to AG number, P =0.028 and 0.008. The multiple regresion analysis showed that PCAR was 1.63 times more effective on AG number than that of TZI. AG number 40 was adopted as the cutoff point of BOO, and PCAR 0.75. The dignsotic correctivity has been more than 90%. Conclusions PCAR measured by TRUS is simple and reliable to detect BOO due to BPH.

Objective To analyze the significance of prostate related factors by TRUS for predicting the outcome of TURP for BPH. Methods Data of 52 patients who had received TURP were studied pre- and 3 months postoperation. Results Significant changes between IPSS,volume of transitional zone,transitional zone index(TZI),presumed circle area ratio( PCAR),Qmax,resistive index(RI),AG of pre- and post-operation were shown.Preoperative PCAR,RI were associated to ?AG (AG pre -AG post )significantly.Multiple regression analysis showed that PCAR and RI were related factors of ?AG.RI affects ?AG 3 times as significantly as PCAR.?AG of the patients with RI≥0.75 was significantly different from that of the patients with RI

Objective To analyze the significance of transrectal ultrasonography (TRUS) for diagnosis of BPH. Methods The data of 92 patients with dysuria were studied,including the case age,history,IPSS and serum PSA level.The volumes of total prostate and transitional zone were measured.The PK 1 and PK 2 of uretheral artery were determined by transrectal color Doppler,Q max and P detQmax were determined by urodynamics.Transitional zone index(TZI),resistive index(RI) and AG value were calculated. Results Correlation analysis showed that TZI( r=0.802,P =0.013),IPSS( r=0.704,P =0.023),RI( r=0.897,P =0.004) were significantly related to AG(AG=P detQmax -2Qmax).Multiple regression analysis showed that TZI and RI were relative factors of AG(R=0.947, R 2=0.897, 0.793, P =0.003),and the standard partial regression coefficients were 0.397( P =0.015) and 0.770( P =0.004),respectively.RI affected AG 1.94 times as significantly as TZI(0.770/0.397).Apart from effect of TZI,RI was the independant relative factor of AG( r=0.785,P =0.004). Conclusions Measurement of RI of prostate urethral artery and TZI by transrectal Doppler ultrasonography can offer valuable help for diagnosis of BPH.

Objective To monitor the production of nitric oxide(NO)and to study its role during ischemia-reperfusion of kidney transplantation in rats using electron paramagnetic resonance(EPR). Methods LEW male rats (age of 8 to 10 months,body weight of 200 to 230 g) were included.Of them 30 were assigned to donor group whose kidney grafts were stored at 0℃ for 24 hours.The remaining 45 rats were equally divided into 3 groups (15 in each group).Group 1 served as controls.In Group 2,allotransplantations of kidneys were performed,and both original kidneys were removed during reperfusions.In Group 3,2 hours prior to the operation,the donors and the recipients were both treated with L-NAME at the dose of 30 mg/kg.Reperfusions were done to the transplanted kidneys and both original kidneys were removed.The production of NO was measured with ERP at each time point before and after blood flow recovery.The creatinine level,GFR and the tissue carbonyl content were recorded on the first and fifth days after operation. Results In Group 2,the production of NO remarkably increased after 15 minutes' reperfusion and kept increasing for 120 minutes. Then the level fell to normal after 210 minutes.In Group 3,the recorded creatinine levels were higher than those in Group 2 at the 24th hour ( P